Cordset hanking machine



May 20, 1958 M. A. SCHOOS EIAL 2,835,089

CORDSET HANKI-NG MACHINE Filed Aug. 1, 1955 6 Sheets-Sheet 1 f/71/6/7 for;

Jain C. Bar/re. 7. Jew

7772/1 ffomey May 20, 1958 M. A. scHoos ET AL 7 2,835,039

CORDSET HANKING MACHINE Filed Aug. 1, 1955 6 Sheets-Sheet 2 fin/e/vzfarax Maz/r/ce A. Jcaas. Jofin C Eur/6?, y W o?- M;

726/) Adda/77g May 1 M. A. scHoos ET AL 2,835,089

CORDSET HANKING MACHINE 6 Sheets-Sheet 3 Filed Aug. 1, 1955 May 20, 1958 M. A. scHoos ET AL 2,835,089

CORDSET HANKING MACHINE 6 Sheets-Sheet 4 Filed Aug. 1, 1955 May 20, 1958 M. A. scHoos ET AL CORDSET HANKI'NG MACHINE Filed Aug. 1, 1955 6 Sheets-Sheet 5 ZMM M y 1958 M. A. SCHOOS ET AL 2,835,089

CORDSET HANKING MACHINE Filed Aug. 1, 1955 6 Sheets-Sheet 6 United States Patent CORDSET 'HANKING MACHINE '"Maufice A. Schoos, Warwick, and John C. Burke, Crans- 'ton, R. L, assignors to General Electric Company, a corporation of New York ApplicationAugust 1, .1955, Serial No. 525,419

9 Claims. (Cl. 53-116) The present invention relates to a semi-automatic machine-for use in processing electrical cordsets of insulated wire having a connector or current tap attached to one end and .an attachment plug at the other. This machine is capable of winding a cordsct into a coil, then wrapping a label around the coiled cordset and stapling ittogether and, finally, it allows the operator to test the cord for circuit continuity, all in a single cycle of the machine.

in the past it has been the common practice to coil the cord in one operation, apply the label in another and, finally, to test the cord in a third operation. This invention has been made to combine these separate operations into a single step controlled by one operator who takes a completed cordset and in a matter of seconds coils it into a bundle, attaches a label for holding the bundle together, and tests the cordset so that it may be stacked in a carton for shipment.

The banking machine of the present invention comprises a rotating spindle having at its working enda crossbar supporting .a pair of parallel winding arms at the ends. A testing device is included as part of one of the winding arms so that the connector end of the cord may be attached thereto. The rotating spindle moves in a clockwise direction to wind the cord over the two winding arms. In order to obtain a bundle which is consistently of standard size for the size of the label and the position of the staples, it has been found necessary to guide the cord onto the winding arms. Thus, a cord guiding mechanism is provided at one side of the machine and it includes a .double flanged roller mounted on a reciprocating shaft and :in engagement with a stationary roller with means for snapping the cord between the rollers and confining it be .tween the double flanges. The shaft of the flanged roller .is associated with a cam that reciprocates the shaft back .and forth along the surface of the stationary roller with the result that the cord is coiled .on the winding arm in several neat layers. Furthermore, it is always necessary to apply tension to the free end of the cord to control it during the winding operation. Accordingly, the cord is fed through a tensioning .mechanism which grips the-cord tightly .as the cord is being coiled on the winding arms.

Since the back end of the .cord is provided with an attachment plug or the like, it is necessary that the cord tensioning mechanism be provided with a shock absorbing means so that the plug does not shatter or become disconnected from the cord when it strikes the tensioning mechanism. As a practical matter it is nearly impossible to manufacture cordsets of the exact same length; therefore, the cord tensioning mechanism cannot be rigidly mounted in any particular location. Thus, the cord tensioning mechanism is slideably mounted on the machine and spring-biased to react against the pulling action of the .cord.

:Labels for wrapping the coiled .cord are automatically fed to the machine from a long strip of labels supported on .a reel, .and an elevating mechanism separates .a sin- .gle label from :the others during each cycle of the machine and raises the label under the cord and folds it to- .gether so that its edges may be stapled together. A pivoted stapler headsupporting a pair of stapling machines is mounted near the top of this machine. The head is movable up and down into engagement with the lalel and it applies several staples after the label has compressed -the mid-section of the coiled cord into a tight bundle. Once the staples are applied, it is then diflicult for the label to slide off of the cord because of the rounded loops on both sides of the label.

It will be readily appreciated by one skilled in this art that in order to properly assemble the labels around the cord and apply the staples, it is necessary that the coiled cord be held in theexact same position each time the labeling and stapling operation is to take place. For this reason, a positive clamping means comprising an air motor and brake shoe is used toact against a flat surface on the side of the rotating spindle to bring the spindle to an abrupt halt when the winding arms are in the proper horizontal position.

The principal object of this invention is to provide a semiautomatic machine for use with electrical cordsets having connector devices at each end so that the cord may be coiled in a uniform manner, a label aflixed, and the cord tested for circuit continuity, all in a single pass through the machine.

A further object of this invention is to provide a cord banking machine wherein the rotating spindle for the winding arms may be stopped abruptly by a suitable braking mechanism so that the winding arms are ina particular predetermined position.

A further object of this invention is to provide a cord hanking machine with a guiding mechanism for feeding the cord onto the winding arms in several neat layers so during the winding operation.

A still further object of this invention is to provide a cord banking machine where the tensioning mechanism is provided with a shock absorbing means to protect the connector device on the remote end of the cord from damage.

Our invention will be better understood from the following description taken in connection with the accompanying drawings and its scope will be pointed out in the appended claims.

Figure l is a perspective view of 'a'completely assembled cordset banking machine embodying our invention.

Figure 2 is a perspective view partially in cross-section showing the cord guiding mechanism comprising in general a double flanged roller and a stationary roller.

Figure 3 is a perspective view partially in cross-section showing the cord tensioning mechanism and the coiled spring which serves as the shock absorbing means of such a mechanism.

Figure 4 is a cross-sectional view of the jaws of the tensioning mechanism of Figure 3 showing a pair of steel balls which are spring biased; the outer ball serving as a latch for the jaws while the inner ball is adapted for gripping engagement with the cord.

Figure 5 is aside elevational view of the label elevating mechanismin its lowered position and flush with the top surface of the table of the machine.

Figure-6 is a view similar to Figure 5 showing the label elevating mechanism in its topmost position with the pivoted fingers being brought into position to :hold the label around the coiled .cord until the staples can be aattached.

Figure 7 is a diagrammatic showing of the air motor Patented May 20, 1958 3. for operating the elevating mechanism, and including the switches, valves and linkage that are operated by the movement of the piston of the air motor.

Figure 8 is another diagrammatic view showing at the bottom the air motor for actuating the rotating spindle containing the winding arms for the cord, and including a switch and air valve which are operated when the piston of the air motor is at the top of its stroke.

Figure 9 is a perspective view showing the pivoted stapler arm and the drive means, one-revolution clutching mechanism and the cam members for raising and lowering the stapling arm and operating the stapling machines.

Figure 10 is a view showing the air motor for actuating the brake shoe which is arranged to move against a fiat surface on the side of the rotating spindle of the machine to bring the winding arms to an abrupt stop when they are in a horizontal position at the end of the winding operation.

Figure 11 is a view show-ing a cordset after it has been packaged on the subject cord hanking machine.

Referring in detail to the drawing and in particular to the perspective view of the complete machine of Figure 1, 10 represents the base of the machine and it comprises a work table 11 over which is horizontally mounted a rotating spindle 12 having a crossbar 13 with a pair of parallel winding arms 14 adjustably supported at its ends. In brief, the dilferent elements which are included in this machine will be described first merelyto orient them, while a detailed discussion of these elements will be made later when each view of the drawing is discussed in turn. Figure 11 shows a cord 15 having an attachment plug 16 at one end and a current tap 17 at the opposite end. A paper label 18 has been tightly folded around the midsection of the cordset and fastened together by means of staples 19 to form a very neat and compact package. Going back to Figure 1, there is provided on the left-hand winding arm 14 a testing receptacle 20 into which the current tap 17 of the cordset is inserted. The rotating spindle 12 moves only in a clockwise direction and it has been found necessary to accurately guide the cord as it is wound on the winding arms in order to apply a tight label over the cordset and fasten the staples close-in to the cord without penetrating the insulation of the cord. This guiding mechanism 21 at the left-hand side of the machine controls the position of the cord as it is laid in neat layers on the winding arms, as will be later explained with relation to Figure 2 of the drawing.

As previously mentioned, if the cord were fastened in the testing receptacle 20 and guided in its movement by the cord guiding mechanism 21 as the winding arms rotate, the free end of the cord with the plug 16 attached would whip around and be in uncontrolled flight. This would result in both danger to the operator, a loosely wound cordset and require the operator to spend time in searching for the plug end of the cord so that it could be tested for circuit continuity. These problems have been solved by installing a cord tensioning mechanism 22 just before the cord enters the guiding mechanism 21, as will be better understood from the discussion of Figures 3 and 4 of the drawing. A female testing receptacle 23 is located on the machine between the guiding mechanism 21 and the tensioning mechanism 22 so that after a complete cycle of the machine, the operator merely reaches toward the tensioning mechanism and removes the plug end of the cord and inserts it into the testing receptacle 23 to complete a circuit through the cord which will energize tell-tale lights 24 in the table 11 of the machine to clearly indicate to the operator the condition of the finished cordset. A long chute or trough 25 is supported on the fioor in an elevated position leading up toward the table of the machine for holding several dozen cordsets laid out lengthwise on top of each other.

This machine is loaded with a cordset when the operator, using her left hand, picks up the current tap 17 of the cordset, transfers it to her right hand and then inserts it '4 in the testing receptacle 20. At the same time, the operators left hand snaps the cord into the guiding mechanism 21 and then into the cord tensioning mechanism 22 and then presses the start button 26 on the front of the machine. In quick succession, the winding arms 14 move in a clockwise direction to wind the cord in neat layers into a bundle. At the end of this winding cycle, the winding arms are brought to an abrupt stop in the same position as shown in Figure l by a spindle clamping mechanism that will be discussed later with relation to Figure 10 of the drawing. A long strip of perforated labels 30 is unwound from a payoff reel 31 that is pivotally supported on a pair of bracket arms 32 at the right side of the machine. This strip of labels is takenofi of the bottom of the reel and fed into the top of the work table 11 so that the first label is located over an elevating mechanism 33 that is centered beneath the winding arms 14. The function of the elevating mechanism is to cut a single label from the strip of labels and raise the label under the mid-section of the coiled cord, fold the label around the cord and compress it slightly while holding the folded edges together until the overhead stapler arm 34 can be lowered and a pair of staples applied to the label. The stapler arm 34 carries a pair of stapling machines 35 at the front, as will be better understood from the detailed discussion of Figure 9 of the drawing. It is after the label is stapled on the cordset that the operator takes the plug 16 and connects it in the testing receptacle 23. If the circuit is complete, the operator merely unplugs the cordset, slips it off the winding arms 14 and drops it into a carton for shipment.

The above discussion is a brief summary of the operation of the cord banking machine embodying our invention, and attention is now drawn to the detailed views of the several operating components which are combined in the beforementioned manner. In the cord guiding mechanism 21 of Figure 2 there is a stationary roller 36 36 rigidly supported from the base of the machine. A drive shaft 37 mounted in suitable bearings has a driven worm wheel 38 at one end and a cam 39 at the other. The wheel 33 is driven by suitable chains, gears and worms (not shown) which are motivated by the same force that drives the rotating spindle 12 of the winding arms 14. The result is that the cam 39 is synchronized with the position of the winding arms 14. A pivoted arm 40 is supported from the shaft 37 and it in turn is the support means for a double flanged roller 41 through the medium of the movable plunger 42. The free end of the plunger 42 is shaped as a cam follower and engaged within the cam track 43 in the side of the cam 39 so that as the cam 39 revolves the position of the flanged roller 41 with relation to the stationary roller 36 will be altered in a predetermined manner. The outer end of the flanged roller 41 has a frusto-conical nose 44 and the roller 41 is held against the stationary roller by means of a tension spring 45 connected between the arm 40 of the flanged roller and the support plate of the stationary roller 36. Hence, it will be clear that the cord 15 is engaged in the cord guiding mechanism 21 by merely wedging the cord between the tapered nose 44 of the flanged roller 41 and the stationary roller against the action of the tension spring 45 until the cord is confined between the double flanges. The tension of the spring 45 is great enough to hold the cord between the double flanges as the roller 41 moves back and forth across the surface of the stationary roller 36.

In the consideration of the cord tensioning mechanism 22 of Figures 3 and 4, there is fixed to the base 10 of the machine a metal tube 46 containing a plunger 47 that is slideably mounted therein. The lower end of the plunger 47 is hollow for receiving one end of a tension spring 48. This spring is fastened in the hollow portion of the plunger 47 and fixed at its other end to the bottom of the tube 46 by means of the pin 49. At the upper end of the tube 46 there is a longitudinally extending asaaosa slot 56 so that a set of fixed jaws 51 may be joined 'with the plunger 47 by a connecting portion .52. The tension spring 48 normally holds the plunger 47 and thus the fixed jaws 51 down at the bottom of the slot 50 in the tube 46.

Figure 4 is a better illustration of the fixed jaws 51.

The mouth of the jaws is closed by a movable steel ball 53 located in one of the jaws and spring biased against the other one. A spring 54 acts against this ball and it in turn is held in place by set screws 55 and 55. This steel ball 53 serves as a latch means so that the cord 15 may be confined between the fixed jaws by forcing the cord to wedge the ball back into its supporting jaw until the cord snaps into place. A tensioning or gripping force is provided by a second movable ball 56 that is spring biased to hold the cord against the opposed jaw. This ball 56 is acted upon by a spring 57 that is held in place by means of set screws 58 and 58. As the machine winds the cord into a coil, the tensioning mechanism 22 serves as a brake to pull back on the cord so that it is tightly wound around the winding arms 14. In actual practice, the cord is in somewhat of a twisted condition when it is taken out of the trough or chute 25 and inserted into the machine. The tensioning ball 56 will tend to straighten out the cord and in doing so the fixed jaws 51 will flutter due to the holding force of the spring 48 until the winding operation is complete. At that time the plug 16 of the cordset will strike the jaws 51 and move the plunger 47 and stretch the spring 48. There is a sop pin 59 in the path of movement of the jaws 51 so that the cord cannot pull the plunger 47 out of the tube 46.

Previously, in the discussion of Figure 1, mention was made of the label elevating machine 33 located in the center of the work table 11. Figures 5 and 6 are side elevational views of the top of the elevating mechanism in the lowered and raised positions respectively, while Figure 7 is a diagrammatic showing of the air motor 60 and piston rod 61 for raising and lowering the mechanism 33. The top of the rod 61 is provided with a carriage 62 that slides on a group of four vertical guide rods 63 arranged at the corners of an imaginary square. These guide rods are likewise supported for'vertical movement in suitable hearings in the base of the machine. A pair of parallel collars 64 and 65 are fixedly mounted on the guide rods 63 and a tension spring 66 is located on opposite sides of the elevating mechanism 33 and joined between the carriage 62 and the lower collar 64. Formed on the upper portion of the carriage 62 is a double pair of pivoted fingers -67 which are normally in an upwardly turned V-shaped relation, as is best seen in Figure 5. Once the airmotor 60 is actuated, the piston rod 61 will rise and move the carriage 62 upwardly. The suspended springs 66 tend also to raise the guide rods 63 until the lower collar 64 is obstructed in its movement at the top surface of the working table '11. However, the carriage 62 will continue to rise against the spring tension of the suspendedsprings 66. It should be mentioned that there is a pair of inwardly facing abutments 68 formed as part of the upper collar 65 'so that when the carriage 62 continues in its vertical movement, the lower ends of the two pairs of pivoted fingers 67 will strike the abutments 68 and pivot away from each other. It should be remembered that there was a paper label supported on the top surface of the elevating mechanism 3:3, as seen in Figure 1, so that as the fingers 67 pivot upwardly above the upper collar 65, they will engage the label and fold it into a sleeve around the midportion of the coiled cord that is suspended between the winding arms 14. The fingers 67 not only wrap the label around the cord, but they compress the cord so that the label is tightly held in place with the folded edges together for receiving the staples that are to be attached, as will be described hereinafter.

Figure 8 is briefly an air motor 70 and piston rod 71 having at its end a rack 72 for engagement with a pinion gear 73. The gear 73 is integral with a larger sprocket wheel 74, and motion is delivered to the rotating spindle 12 at the top of the figure through a train of chains, gears and sprocket wheels, all in a well-known manner to one skilled in this art. A suitable ratchet type arrangement (not shown) is used so that the rack 72 will only drive the spindle 12 when the rack is moving upwardly, there being vno motion transmitted to the spindle 12 when the rack is lowered to its starting position. A more .detailed discussion of the diagrammatic Figures 7 and 8 will be found hereinafter.

In the discussion of Figure 1 mention was made of the use of a stapler arm 34 carrying a pair'of standard heavyduty stapling machines 35. Looking .at the back of the machine in Figure 9 there is illustrated a shaft 76 mounted in suitable bearings and supporting a small cam 77 and a larger cam 78. A continuously operating electric motor 79 supported on the side of the machine has a speed reducing box 80 and drive shaft 81 which is connected to the shaft 76 by means of a one-revolution clutch 82 that is operated by suitable linkage (not shown) when the elevating cylinder 60 is at the top of its stroke, as will be better explained later. The arm 34 has an offset plate 83 extending downwardly from its pivotal axis 75. The large cam 78 has a cam track 84 located on one side so that the free end of the plate 83 serves as a cam follower 85 that is engaged in the cam track 84 to raise and lower the stapler arm at the appointed times. Pivoted links 86 extend over the operating heads of the stapling machine 35 and are operated by a suitable set of links and bell crank levers 87 which cooperates with the beforementioned small cam 77. Furthermore, there is a counterweight 88 connected by a link 89 to a bracket 90 joined to the stapler arm 34 to counterbalance the weight of the arm. The motor 75 is continuously energized and for very cycle of the machine, the one-revolution clutch 82 is operated to .turn the shaft 76 through a complete revolution which first lowers the stapler arm 34, operates the stapling machines 35 and, finally, returns to its upper position.

In the general discussion of Figure 1, it was stated that the winding arms 14 have to be stopped in a horizontal position with the testing receptacle 20 always on the left-hand side. This requirement is an-essential one since the label must be wrapped around the cordset and staples applied to leave very small clearances. In Figure '10 there is shown a portion of an air motor 92 having a piston rod 93 with a brake shoe 94 on its free end. The right-hand portion of this figure shows the main spindle 12 having a splined hub 95 arranged on the spindle. One portion of the hub has a flat side 96 so that'at the precise moment when the winding arms are approaching their horizontal position at the end of the winding cycle, the air motor 92 is suddenly energized to force the brake shoe 94 against the fiat surface 96 to bring the spindle 12 to an abrupt halt.

Now that all of the elements of the machine have been described in some detail, it is well to refer back to the diagrammatic views of Figures 7 and 8 for an understanding of the sequence of operation of a complete cycle of this machine. Considering first Figure 8 and the air motor 70 for operating the spindle 12 and consequently the Winding arms 14, rod 71 moves vertically until it reaches the top of its stroke. A one-way dog 100 that is pivotally mounted on the top of the rod 71 will first actuate the micro-switch 101 which energizes the air motor 60 of Figure 7 for raising the elevating mechanism 33. Almost simultaneously, a fixed dog also on the top of the rod 71 will actuate the air valve 103. This valve is connected to the air motor 92 of Figure 10 which moves the brake shoe 94 into clamping engagement with the hub 95 to bring the spindle 12 to an abrupt halt. In Figure 7, the piston rod 61 will rise to move the elevating mechanism 33 from the lowered position shown in Figure '4 to the raised position shown in Figure 6 when the pivoted fingers 67 hold the label around the mid-section of the cordset. As the piston rod 61 reaches the top of its stroke, it will engage a linkage arrangement 104 which consists of suitable links, bell crank levers and the like (not shown) for operating the one-revolution clutch 82 of Figure 9. When this clutch 82 is engaged, it sets into motion the shaft 76 which in turn through the cam 78 and offset plate 83 will move the stapler arm 34 down into its operating position. Then at the proper time the small cam 77 will actuate the linkage mechanism 87 and operate the stapling machines 35 to staple the folded edges of the label around the mid-section of the cordset. On the periphery of the large cam 78 there is mounted a fixed dog 106 which actuates a micro-switch 107 at the end of a complete revolution to reverse the operation of the elevator air motor 60 to return the pivoted fingers 76 to their lowered position of Figure 5. As the piston rod 61 descends, there is a one-way dog 108 mounted on the lower end of the rod which trips the micro-switch 109 which is connected with the winding air motor 70 to return the rack '72 to its lowered position. As the rod 61 continues to descend, it comes to rest with the one-way dog 108 engaging the interlocking microswitch 110 while a separate fixed dog operates the air valve 111. The function of the switch 110 is to insure that the elevating mechanism is in its lowered position before the winding air motor 70 can be actuated. If switch 110 is not closed, it is not possible to operate the motor '70. The air valve 111 is connected with a suitable label-feeding mechanism in the table 11 of the machine for feeding a single label over thetop of the elevating mechanism 33 at each cycle of the machine.

Accordingly, having described our invention of a novel cord hanking machine, it should be readily appreciated that this invention is both reliable in operation, simple to load and a great time saver in the packaging of electrical cordsets. Unnecessary lost motion has been eliminated by combining the features of coiling the cord, applying the label and testing the cord all into one machine operation which both saves labor, factory space and provides for better working conditions.

Modifications of this invention will occur to those skilled in this art and it is to be understood, therefore, that this invention is not limited to the particular embodiments disclosed but that it is intended to cover all modifications which are within the true spirit and scope of this invention.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. A machine for hanking a cordset having a plug at one end and a connector at the other comprising a rotating spindle having a pair of winding arms, one end of the cordset being connected in a receptacle on one of said arms, reciprocating guide means for feeding the cord onto the winding arms as the spindle is driven, and a spring-biased cord tensioning mechanism for gripping the cord during the winding cycle, the said spring biasing means serving to absorb the shock of the connector device on the free end of the cord striking the tension mechanism, and brake means for engaging the rotating spindle to bring it to an abrupt stop with the winding arms arranged in a predetermined position.

2. A cordset banking machine as recited in claim 1 wherein there is provided an elevating mechanism for folding a label around the cordset once the winding cycle has been completed, and a movable stapler arm which is adapted to be brought into position over the folded edges of the label so that the label may be stapled around the cordset.

3. A cordset hanking machine as recited in claim 1 wherein the reciprocating guide means comprises a double flanged roller which is pivotally mounted on a hinged arm, and spring means connected to the hinged arm for holding the flanges of the roller in engagement with a stationary roller so that the cord is confined between the double flanges of the roller and the stationary roller by pivoting the flanged roller against the action of the spring biasing means, and cam means for moving the flanged roller across the stationary roller.

4. A cordset hanking means as recited in claim 1 wherein the cord tension mechanism comprises a slideable member having a pair of fixed jaws with a latch means at the mouth of the jaws and a tension means toward the base of the jaws so that the cord may be snapped past the said latch means to be engaged by the tension means to provide a predetermined tension on the free end of the cord during the winding cycle.

5. A cord hanking machine as recited in claim 4 wherein the said latch means comprises a spring pressed ball located in one of the jaws and biased into contact with the other, while the said tension means also comprises a spring pressed ball.

6. A cordset hanking machine comprising a rotating spindle having a pair of winding arms, reciprocating guide means for feeding a cord onto the winding arms as the spindle rotates, a resiliently supported cord tensioning mechanism for gripping the cord and holding it taut during the winding cycle, and brake means for engaging the rotating spindle to bring it to an abrupt stop in a predetermined position at the end of the winding cycle, an elevating mechanism for raising a label toward the winding arms and adapted to wrap a label around the mid-section of a cordset, and a movable stapler arm that may be brought down into position over the folded edges of the label so that the label may be stapled onto the cordset.

7. A cordset hanking machine as recited in claim 6 wherein one of the winding arms supports a testing receptacle for receiving a connector device mounted on one end of the cordset while a second testing receptacle is located on a fixed portion of the machine for receiving the connector device on the opposite end of the cordset so that the circuit continuity of the cord may be tested after the staples are fastened to the label.

8. A cordset banking machine as recited in claim 6 wherein the said reciprocating guide mechanism comprises a double flanged roller and a stationary roller and means 'for moving the flanged roller back and forth I across the surface of the stationary roller.

9. A cordset hanking machine as recited in claim 8 wherein the double flanged roller is supported on a pivoted plate which is spring biased toward the stationary roller, one side of the flanged roller having a nose of frusto-conical shape so that a cord may be inserted in this guide mechanism by forcing the cord against the nose of the flanged roller until the cord snaps between its double flanges.

No references cited. 

